Back-stop attachment for paper-feeds.



F. A. HAZARD. BACK STOP ATTACHMENT FOR PAPER FEEDS. APPLICATION PILEDSEPT. 28, 1909.

Patented Jan. 9,.1912.

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FRANK A. HAZARD, on NEW YORK, n. Y., ASSIGNOR T0 aosnrn r. KAVENAUGI-I,on

new YORK, n. Y.

BACK-STOP ATTACHMENT FOR PAPER-FEEDS.

Specification of Letters latent.

Application filed September 28, 1909. Serial No. 520,012.

To all whom it may concern:

Be it known that I, FRANK A. HAZARD, a citizen of the United States ofAmerica, and a resident of the city,county, and State of New York, haveinvented certain new and useful Improvements in Back-Stop Attachmentsfor Paper-Feeds, of which the following is a specification.

This invention relates to paper separating mechanisms and refers inparticular to the back stop mechanism ormeans for retaining theuppermost sheets of paper as the top sheet is being removed.

The particular objects of the invention as well as the means foraccomplishing the same are fully set forth in the followingspecificationand will be easily understood by reading the same in connection with theaccompanying sheet of drawings in which my invention is disclosed in theform of a back stop attached to a separating mechanism.

In the said drawing Figure 1 is a side elevation of a portion of a paperseparating mechanism provided with a back stop embodying my invention.Fig. 2 is a perspective view of the backstop and Fig. 3 is a sectionalview on line 3-3 of Fig. 1.

Referring first to Fig. 1 the reference numeral 4 denotes a stack ofpaper suitably supported on a platform 5 which preferably is of the typeoperated vertically by weights or the like so as to always keep the topsheet at the same level. 6, 6 indicate standards connected on each sideby a rod 7 upon which reciprocates a separating means comprising thecarriage 8 and separating roller 9. As this latter is moved over thestack of paper it combs out the sheets over the shelf 10 as shown, untilfinally the top sheet 11 is removed by feeding means not shown. Theseparating means may be operated in any suitable manner and the meansfor doing so need not be shown, nor described in detail. The saidstandards support transverse rods 12, 12 to which are fastened brackets13, 13 supporting the guiding rod 14. Upon this latter is adjnstablyfixed the back stop casing 15 by means of a set screw 16. Said casing isprovided with sockets 17 for the reception of the plungers 18, each ofwhich carries two cam rollers 19. Each plunger further supports a pin 20having a head 21. The pin is movably carried in the plunger as shown andbetween the latter and the head 21 there is an expansion spring 22. Inorder to operate the plungers I provide a slide 23 having a cam 24. Theslide is provided with flanges 25 sliding under the gibs 26 which latterare secured to the casing by screws 27. The slide is operated from theaforesaid carriage 8 by means of a' connecting bar 28 fast to the arm 29secured to the carriage. The bar 28 is slotted and the slide is providedwith a plurality of holes 30 so that these two members may be adjustedwith relation to one another, and fastened by a screw 31.

The operation is as follows: The carriage 8 is reciprocated to cause theroller 9 to comb the sheets and through the instrumentality of the arm29 and connecting bar 28 the slide 23 with cam 24 is reciprocated in thecasing 15 and between the rollers 19, causing the plungers 18 to bereciprocated vertically in succession so that as the sheets are beingadvanced by the separator, the plungers are operated to cause the pinsto engage the rear edge of the sheets next to the top one. In thismanner the sheets are being held firmly while the top sheet is beingremoved-by any suitable feeding means not shown-and practically assuringof but one sheet being removed at a time.

In Fig. 1 the separator is shown in the middle of its forward stroke-tothe left. Thus it will be seen that when the top sheet is advancedbeyond the shelf 10 the plungers will all be in their lowest positionand the pins firmly engaging the paper, and on the rearward, to theright, stroke of the separator the pins will be raised and remain upuntil the separator has again advanced the top sheet. Then the plungerswill again descend to hold the suceeding sheets. During this operationit will be noted that the cam 24 supports the pins in theirupperposition. The sucessive disengagement of the pins with the pile isfor the purpose of holding on to the sheets as long as possible untilthe top sheet is finally separated. The spring seated pins 20 are ofvital importance. They are of such lengths that the heads 21 will alwaysengage the paper, but if the level of the stack should vary, then thesprings permit the pins to adjust themselves. This assures a positiveand elastic touch of the pin heads upon the paper. If the plungers acteddirectly on the paper a very fine adjustment of the lifting of the paperwould be necessary in order to insure that the sheets would be preventedfrom following the top sheet, and on the other hand to avoid unduestrain on the back stop mechanism. Attention is also directed toward theadjustability of the cam stroke in the casing. For instance, it may beadjusted to cause a long dwell to the plungers when the latter are inthe upper position only. This is particularly advantageous when thepaper is slow to separate as it gives the member 9 plenty of time toact. This renders the device specially adaptable to various kinds ofseparating mechanisms. I may of course use any number of plungers and inother details vary or change the construction set forth, but I claim allsuch changes or alterations as properly come within the scope of theclaims.

I claim 1. In a back stop mechanism the combination of a sheet advancingdevice, a plurality of pins adapted to engage the top sheets of a stackof sheets, a reciprocating cam for engage the top sheets of a stack ofsheets and means for causing the said cam to travel a distance equal tothe distance of travel of the said device.

3. In a back stop mechanismlthe combination of a plurality of pins, acam, a sheet advancing device, means for reciprocating the cam from thesaid device to cause the said pins to be lifted successively in such amanner that the pin nearest the sheet advancing device is lifted first.

Signed at New York, N. Y. this 21 day of September 1909.

FRANK A. HAZARD.

Witnesses:

IVAN KONIGSBERG, K. G. LEARD.

Copies of this patent may be obtained for five cents each, by addressingthe f'flommissioner of Patents Washington, I). G.

